Hydrochloric Acid → (1,1-Dioxo-1,4-dihydro-1lambda6-benzo[1,2,4]thiadiazin-3-yl)-acetic acid

HRID 424224Notes

Reaction equation

[OH-].[Na+].C([O:5][C:6](=[O:21])[CH2:7][C:8]([NH:10][C:11]1[CH:16]=[CH:15][CH:14]=[CH:13][C:12]=1[S:17](=[O:20])(=[O:19])[NH2:18])=O)C.Cl>O>[O:19]=[S:17]1(=[O:20])[C:12]2[CH:13]=[CH:14][CH:15]=[CH:16][C:11]=2[NH:10][C:8]([CH2:7][C:6]([OH:5])=[O:21])=[N:18]1

Participants

Conditions

Temperature: 110 °C

Procedure

Solid sodium hydroxide (3.48 g, 87 mmol) was dissolved in water to make a saturated solution. The crude N-(2-sulfamoyl-phenyl)-malonamic acid ethyl ester was added into the sodium hydroxide solution. The reaction mixture was heated at 110° C. for 2.5 h, and then was cooled down to 25° C. The reaction mixture was acidified by slowly adding a 12.0 M aqueous hydrochloric acid solution (9.67 g, 116 mmol) while cooling in an ice-water bath. The product precipitated and was collected by vacuum filtration. The solid was washed with cold water and dried under high vacuum to afford the crude product, (1,1-dioxo-1,4-dihydro-1λ6-benzo[1,2,4]thiadiazin-3-yl)-acetic acid (5 g, 20.8 mmol, 71.7% over two steps), as a white solid. 1H NMR (400 MHz, DMSO-d6) δ: 3.58 (2H, s), 7.31 (1H, d, J=8.0 Hz), 7.44 (1H, dd, J1=7.8 Hz, J2=7.8 Hz), 7.67 (1H, dd, J1=7.8 Hz, J2=7.8 Hz), 7.79 (1H, d, J=7.9 Hz), 12.18 (1H, bs), 13.03 (1H, bs). LC-MS (ESI) calcd for C9H8N2O4S 240.02, found 241.1 [M+H+].

Workup

temperaturewas cooled down to 25° C
temperaturewhile cooling in an ice-water bath
customThe product precipitated
filtrationwas collected by vacuum filtration
washThe solid was washed with cold water
customdried under high vacuum

Sources & evidence

ORD record: ord-745aaffbf5c5438282b6271f3cb5eb0d
Source dataset: uspto-grants-2012_01
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08101800B2

Reaction notes

Loading…